Help me choose the right wang errr I mean wing
 

Hey guys,

Im looking into developing the aero on my track toy. at this point it has a GV front lip, I know useless, and a sizeable ducktail bolted to the trunk lid. I will be adding a sizeable splitter this offseason along with front tire spats and potentially canards, my main question is the rear. Im debating between the GTC200 and GTC300 wings that 949 offers on their site. The car currently sits at around 220 whp/230wtq on a very conservative tune to preserve the rods. The tires I use are 205/50/15 SM6/7 takeoffs on x8 wheels. I do plan to do rods on the motor eventually and up the power however I dont plan to change the turbo setup so I imagine I will peak somewhere in the mid to high 2xx whp. Based on Emilios recommendations on 949s site it seems that the GTC300 really should be used on cars with 300+whp, however I have seen local s2000 guys with relatively stock power run these wings with great success despite the additional drag penalty.

Basically aero wizards, which of the 2 wings should I go with and should I use any sort of risers in conjunction with it.

GTC200 & call it a day :)

I don't know enough to add useful input but with the Singular endplates it seems like the 200 would be perfect. At least, that is the direction I am headed.

Also according to 949 logic: Small wings are balanced well with just airdams and undertrays.
So if you plan on more front downforce than that, go bigger out back too.

I'd go gtc300 or CoT if you plan on a splitter. Less angle of attack needed for same downforce @ less drag.

https://www.miataturbo.net/attachmen...ine=1414098018
this is what the front aero will look like if that is of any help.

I would cast my vote for the GTC-300 (assuming mounted below roof height) as the best pairing with the front aero you have planned and that is offered (through 949) with miata-specific mounts. You're also well into the power range that would make use of it in my opinion/experience.

The 200 pairs well with an airdam/no splitter. With proper front aero you'll end up with a GTC-200 jacked up on multiple risers, with big endplates and lots of angle. I'd prefer to buy a wing with some headroom that balances with the front at a minimal angle - then you've got room to play with less/more angle as you tweak the setup in the future.

Aero is like boost - you think you'll be happy with a certain amount, but you always want more more more. It's incurable ;) so my advice would be don't paint yourself into a corner by making a big purchase that doesn't give you room to grow.

The step beyond that for BIG downforce, is 2D wing mounted high/far back, but the GTC-300 has a lot to offer.

edit: forgot you asked about risers. You're going to want a set of risers for either the 200 or 300. Some guys double up on risers with the 200 in an effort to get the most performance out of it that they can. IIRC, double risers still puts it below roofline by a couple inches, which is about the max height you want with the 3D design.

-Ryan

Good post except for this part. You do NOT want to mount the wing far back. Optimally it would be directly over the rear axle and the further back you put it the more your rear downforce reduces your front downforce due to leverage. Also the higher you mount it the more your wings drag removes downforce from the front for the same reason, but high mounting is almost always worth it.

IMO you always want a 2d wing. I'd only run a 3d wing if it was specifically designed for at least the base of the windshield back on my car. IE a 3d wing for most of you would need to be designed on an NA/NB miata with a hardtop on. Installing a 2d wing is like putting in a set of universal fuel injectors (you have to adjust your tune and make the mounts match up), installing a universal 3d wing is like slapping some random tune from some car that may or may not be a miata into your mega squirt and just adjusting it for the size of the injectors you have.

I feel like it would be in the spirit of your build to make a dual element wing out of ebay wings with home made endplates.

Do you have a specific EBAY wing in mind? We used to be able to get cheap Chinese CF airfoils to make into wings, but I think they're gone. Got a link for what you're referring to?

Not really. The downside to the ebay wings is who the fuck knows anything about the aerofoil besides the fact that it was probably copied from a name brand wing of some sort. And they're all narrow. There's some ricer wings that are injection molded plastic that should be strong enough or would easily be made strong enough with a single wrap of fiberglass, and they look to have copied the one of the apr 2d wings. But they're harder to find than the ones that look like they copied the apr 3d wings. You dont want the aluminum extruded ebay wings.

I don't suppose anyone has gone as far as datalogging damper travel front and back with various aero configurations to deduce downforce? That sort of empirical data is usually limited to kinda-high budget race teams and outside the normal realm of the average DIY enthusiast.

Speaking in terms of taking each concept to the extreme, yes. However, in my post I'm referring to a more down-to-earth range of what someone will likely do. Most of what I'm going to say following this, you are well aware of but I'm posting it as info for others who follow the conversation...

As you certainly know, moving the wing back is done for much the same reason as moving it higher - to get the 2D wing out of the area behind the cabin which has a complex combination of different airflow directions which it is not designed to operate in (whereas 3D wings are designed for this area). Within a reasonable range - longtails and uprights that reach back at a 30* angle aside - the benefits of getting the wing into more unidirectional airflow are far outweighing the drawback of a see-saw effect of force behind the rear axle.

Also as an aside, doesn't the suspension act to reduce this effect? - dramatically moreso than if there was no suspension and simply a hard pivot point at the rear axle.

The frame rail mounts that were used on Crusher for their GT250 are good example of probably the outer range of how far back you want to take a wing before the effect does become apparent. But even that is substantially far back compared to what can be accomplished with anything that mounts to the trunk area. My uprights which go to the trunk (and then are reinforced to the top of the frame rail) reach back at almost 45* and still don't place the airfoil quite as far back as the example on Crusher.

https://www.miataturbo.net/attachmen...ine=1414172155

Again, on a very broad basis when speaking of ALL 3D wings, yes ideally they should be designed for a particular vehicle shape and height/orientation relative to that car.

However, if you narrow the discussion down to the APR series of 3D wings, it has been found through quite a lot of various experiences from many people over the years, that the GT-200 and GT-300 shapes work quite well on a miata. If we start talking about some other 3D wing out there, we have far less experience within the community to draw on, but these in particular are not the wild cards that you make them out to be.

-Ryan

What about the Blackbird Fabworks Lexan Spoiler?

The GTC200 and 300 do have one thing that most 3d wings dont. They're made in a large enough quantity that the biggest drawback of the 3d wing is reduced enough to be stomach-able, to the point where they're actually cheaper than APR's 2d offerings.

Probably the most effective single rear aero mod available short of going to a wing IMO. I ran a similar spoiler for a couple years and there's a reason this spoiler style is standard issue for the Super Miata series - less $$ than a wing since the series' goal is to be low-cost of entry - and lots of benefit. Adjustability is important as different angles make big differences.

A spoiler isn't a replacement for a wing - more of a stepping stone if you will or a good pairing for a car that has minimal front aero. Martin (the OP) already has a spoiler and is looking to move up to more downforce.

Those who already have a spoiler shouldn't yank it when they move up to a wing - experiment with dropping the spoiler to a very shallow angle (almost flat) under the wing and win :)

-Ryan

I've been trying to convince an XP competitor who is adding a wing to keep his current spoiler (used to be an FP car).

My impression was that a spoiler has more downforce than a wing. but it has significantly more drag.

No way, spoiler isnt even close to being able to generate the same amount of downforce as a wing.

how do you know everything? are you just guessing or what? anyway the guys that told me that work here
https://www.miataturbo.net/attachmen...ine=1414179974

K.

Empirical evidence.. bolt on a spoiler and feel a nice bump in rear-end stability/grip on a car with little/no other aero. Improve front aero, find yourself wishing for more rear grip again. Bolt a big wing onto the same no-aero car, understeer wildly into some parallel universe. Build front aero to match, win.

-Ryan

On the spoiler discussion: It seems like they can make good down force at low speeds but have excessive drag at higher speeds (good for autoX). So how would a DRS (actuate the spoiler flat to reduce drag at high speed straights) on a rear spoiler similar to the BlackBird one compare to a APR 2D wing on a track. Could this be a best of bet world solution assuming the control system is well tuned and the actuation is sufficiently quick. This is a project I've been considering tackling in the future.

you need a wing slider -
https://www.miataturbo.net/attachmen...ine=1414181575
JOES Racing Products 25983

I ran a spoiler at ~35* (fairly steep) at many full-size tracks and up to about 130mph. I saw more downforce from a COT wing (which is a relatively low-downforce, low-drag design). YMMV?

A much better avenue to explore IMO is a wing that will produce all the downforce desired which actuates to a shallow angle on the straights. Keith Tanner has been playing with this type of system:
https://www.miataturbo.net/race-prep...ng-test-74913/

They do not give any specs on actuation speed with that. I'm not sure if it would make a suitable DRS actuator. It might just allow for slow adjustments then lock in the setting rather than repetitive quick actuations.


But hardware aside... I'm considered more about the actual theory of a DRS spoiler miata than the hardware side of things at the moment

i'm never listening to roman again... that's for sure. :/

Its because you didnt go bowling with him.

So if the spoiler had more Down force at those high speeds it most likely has more drag. If your not traction limited on the straight why not use DRS on a spoiler to reduce your Down force and therefore reduce your drag as well to help use more of your power for acceleration rather than overcoming the drag force.

what you just described is drag reduction system. More downforce when you need it, less drag when you don't

Woops one inacuracy in my previous post:

What I meant to say was that Keith's been experimenting with actuators on wings, but not quite the same function as I suggested. His is a version that operates as an air brake, whereas I'd like to see a wing that decreases angle by a method of driver-controlled input on the straights to r educe drag.

That makes more sense. Now we're on the same page.

Ya I was wondering why keith went with an air brake system. Maybe it was easier control system to implement based off brake pressure or something.

You may be misreading my post. I'm saying even at 35*, the spoiler did not seem to provide the same downforce that a wing did. This is not back-to-back same day tests, but same tracks over a span of time as I increasingly added aero to the car. I do not feel any confidence that a spoiler at any angle could balance with the front aero I have now (and there is still much more room for increasing front downforce).

Also, there are triple-digit turns aplenty at the racetrack. I wouldn't be too excited about a spoiler system that decreases angle according to speed, and leaves me with an unbalanced car in the high speed sweepers.

-Ryan

ya, sorry i did misread that. From what I understand, spoilers work well at lower speeds and have very high drag at larger speeds. A wing is a better aero solution overall, but especially better at high speeds with it's downforce to drag trade offs. But you pay for that benefit with it's cost and difficulty in mounting properly.

Yup, I considered that issue. For mid corner stability I was planning on having steering angle as one of the control inputs. ie: do not actuate flat when steering angle is greater than X degrees.

Back to the OP's question:

It sounds like a 2D wing works best if you can get it high enough above the vehicle to see an un-disruption air stream (ie: at level or above the hard top)

The reason for the 3D wing's shape is to attempt to optimize the airfoil shape for the varying streamline directions closer to the trunk lid, caused by air flowing over the car's body. see the video bellow for a good explanation. :bigtu:

i see no video :(

idk works for me.

"http://www.youtube.com/watch?v=SeKKzFSNRFo]APR 2D wing SuperMiata Crusher - YouTube"

looks like 3D for me. did everyone see that there is a new gt250 wing out. seemed to have substantially more downforce and allot less drag.

Here is a good tech article fro APR of the 3D wing. They use a 15 degree greater Angle of attack increase at the outer edge compared to the inner. It's really hard to say which is better without air tunnel testing for your specific vehicle. Personally, I would go with the 2D wing mounted higher up.

http://www.aprperformance.com/index....sk=view&id=181


A good visual of the air streamlines:



https://www.miataturbo.net/attachmen...ine=1414189929

https://www.miataturbo.net/attachmen...ine=1414189929

So concensus is gtc300 ?

Opinions on this one?

Fiberglass CCP Fab Race Car Wing | eBay

That is the choice I made based on my cars latent potential and me trying to utilize it in the future when I get my potential up to the car.

Would like more info as well.

You can not look at a picture of a airfoil and tell you if its good or not (maybe unless you design them for a living or something and have enough experience). It requires air tunnel testing or an exact model to run CFD analysis. If the company knows what they are doing and actually engineered it, they will release a report with the product similar to the APR one. If they don't they probably just reverse engineering some other design making it a guessing game of how good of a copy it is. There's a reason why APR wings cost what they cost, they have engineering time put into their design.

So in summary, either someone has that exact wing and can chime in or you should buy one for yourself, or you buy it and test it and let us know how it goes.

I think when the ad says designed by NASA they mean NACA which means that profile should be in the NACA database and you should be able to figure out what profile it is and how good it is.

Found this while browsing English Racings site: Trunk Spoiler-Wing :: CLEARANCE & USED PARTS no idea if it would be any good for laz. Thought I would throw it out there though.

Bumping this thread instead of starting a new one.

Does anyone have pictures of the miata-specific APR GTC-300? I've tried searching here and with google image search but all the pictures I'm finding look like a GTC200. The APR website shows that the GTC300 has angle adjustment via multiple mounting holes on the uprights, but the pictures I'm finding for "miata GTC300" show angle adjustment via turnbuckles like the GTC200.

I believe the Slickauto car was running a 300, it's an APR sponsored car and the wing is visibly wider than the old v1 200 that was out at the time of that car's building. Unfortunately all the pics I can find of that car are low res but it doesn't look like there are turnbuckles on the back there:


https://www.miataturbo.net/attachmen...ine=1434995790

edit:

I think William was also running a 300 on his old car;

http://949racing.com/server/track/mr...lwilliam_1.jpg

Yeah, that one doesn't appear to mount to the trunk lid which makes me think it's a universal GTC300. I'm wanting to see the miata-specific uprights that bolt to the edges of the trunk lid.